Atoms of Light Acting as Particles

A. P. Kazantsev

The forces acting on a resonance particle in the fields of laser radiation sources can be large. Acceleration, heating, and cooling of atoms by using these forces are discussed. Since the forces are of a resonance type, one can employ them to separate isotopes and excited atoms from unexcited atoms. Light pressure can play an important role in the spectroscopy of narrow atomic and molecular resonances. The quantum features of the motion of particles in a standing light wave are manifested in a fine structure of the absorption coefficient. This review is concerned with analyzing the resonance light-pressure forces and discussing the application of them in optics and quantum electronics.

Peter Franken

Vladan Vuletić, Steven Chu

We point out a laser cooling method for atoms, molecules, or ions at low saturation and large detuning from the particles' resonances. The moving particle modifies the field inside a cavity with a time delay characteristic of the cavity linewidth, while the field acts on the particle via the light shift. The dissipative mechanism can be interpreted as Doppler cooling based on preferential scattering rather than preferential absorption. It depends on particle properties only through the coherent scattering rate, opening new possibilities for optically cooling molecules or interacting atoms.

Abdul Al-Azzawi

The particle nature of light is well known and has important applications. There are two accepted behaviours of light to explain the dual nature of light. In some cases, light acts like a particle, and in others, it acts like a wave. The proof of the wave nature of light came with the discovery of interference of light and diffraction. In this chapter, the wave nature of light will be studied with emphasis on two important wave phenomena, the diffraction and interference of light.